Methods and materials for the reduction and control of moisture and oxygen in OLED devices

ABSTRACT

Novel uses and methods of use for inorganic and macroreticulate polymer bonding to metals to control moisture and oxygen in OLED, and other like devices, are provided. Materials having color change capacity are also provided for the removal of moisture from an OLED, where the material changes color upon reaching its capacity and thereby signals the user that the OLED is no longer protected from moisture damage.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present nonprovisional patent application claims priority to U.S.Provisional Application Ser. No. 60/480,919, filed on Jun. 23, 2003,entitled; METHOD AND MATERIALS FOR THE REDUCTION AND CONTROL OF MOISTUREAND OXYGEN IN OLED DEVICES, which is herein incorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates to limiting damage caused by moisture,oxygen and other like oxygenated contaminants to OLED (organic lightemitting diodes), organic transistors, flat panel displays, and otherlike electronic devices.

It is known that performance of electronic devices can be impaired bycontact with moisture, oxygen and other oxygenated species. For example,semiconductor devices are undesirably oxidized by water and oxygen, andthereby degraded during contact with the same. The damage to thesedevices can be caused by as little as trace levels of thesecontaminants, thereby exacerbating this problem.

OLEDs are optoelectronic devices based on small molecules or polymersthat emit light when an electrical current flows through the device. Thedevices are commercialized in the area of displays, screens, and signs.In addition, several products are commercially available in the area ofcell phones, stereo displays, monitors, and military applications. Ingeneral, these devices incorporate Indium-Tin-Oxide (ITO) films, aconductive transparent film, as the anode, and a thin film of elementslike Ba, Ca, Mg, Al, and the like, as the cathode. Sandwiched in-betweenthe electrodes are carbon based films. The organic films consist of ahole injection layer, a hole transport layer, an emissive layer, and anelectron transport layer. Polymer layers are used to transport theelectrons and holes that are injected into another polymer film such asa polyphenylenevinylene or a “small molecule” organic film such asrubrene or Tris(hydroxyquinolato) aluminum. Light of any color can begenerated by the polymer film or “small molecule” by selecting differentpolymers, dopants for the polymers, or different small molecules.

One recurrent problem of conventional OLED's is their apparent limitedlifetime. The ‘brightness’ of the device decreases over the course ofseveral months as a result of pixel shrinkage causing the quality of theproduct to diminish and eventually become non-useable. Generally, pixelshrinkage within the OLED is associated with moisture and other likecontamination, where moisture permeating through encapsulating materialsand sealants interacts with pixel materials, i.e., moisture degrades theOLED by degrading the hole transport material or causing the cathodematerial to delaminate and degrade. Moisture may also directly attackthe light emitting molecules.

To overcome this problem in the industry, desiccants have been includedin one form or another within OLEDs. For example, solids such asalkaline metal oxides, alkaline earth metal oxides, sulfates, metalhalides, alkali metals, alkaline earth metals, aluminum carbide,aluminum-magnesium alloy, barium nitride alloy, and perchlorate-baseddesiccant materials have been used to protect OLEDs from damage causedby moisture. In some cases these desiccants are blended with binders toremove moisture from environment surrounding the OLED. However, thesesolid materials generally have low surface area, and not enoughcapacity, to capture the water continuously permeating from the outsideenvironment into the interior of the OLED. Additionally, these solidmaterials do not have the capability to remove oxygen that permeatesinto the device and thereby causes performance degradation.

An alternative approach to removing moisture from an OLED environment isto use a lithium metal and magnesium metal deposits. However, thedeposited lithium and magnesium materials do not have high surface areasto capture impurities, i.e., have low capacity.

Finally, the use of silica and zeolite that generally have high surfacearea have also been used to remove moisture from OLED's. However, thenature of these materials to capture the moisture via physicaladsorption does not provide enough efficiency to protect the OLED forlong periods of time. Also, these materials tend to emit moisturedepending on the temperature condition of the device environment, wherethe materials are being employed due to the adsorption equilibrium.

In addition, some of the aforementioned desiccant materials do not haveany capability, or very low capacity, for removing oxygenated speciesother than water. Therefore, damage to these devices caused by otheroxygenated species are not minimized by the above described desiccants.

In all such cases regarding the removal of moisture from an OLED, therecontinues to be a need in the art for more effective removal techniquesof moisture, and other oxygenated species, from the environment of adevice.

In addition, there is a need in the art to have a signal or indicationas to allow the user to determine if and when a device is in jeopardy ofbeing damaged by moisture and other contaminants. In such case, a usermay be alerted to the impending reduction in device quality due tomoisture damage, and not spend additional time or money attempting todiagnose these problems. Against this backdrop the present invention hasbeen developed.

BRIEF SUMMARY OF THE INVENTION

An embodiment of the present invention provides materials and methodsfor removal of water and other oxygenated species from OLED and otherlike moisture and oxygenated species sensitive electronic devices. Inparticular, methods and compositions are provided that can increase thelife-span of an OLED with materials that remove water and oxygenatedspecies substantially irreversibly with highly efficiency and with highcapacity. One embodiment of the present invention enables the removal ofwater and other oxygenated species down to part per billion (ppb) andeven part per trillion (ppt) levels within the device. These results aremuch more effective than using other physical sorption based prior artdesiccants.

The present invention also provides methods and compositions thatindicate when the compositions and methods of the present invention havereached their capacity, and are no longer effective at removing moistureand other oxygenated species from the electronic device's environment.In one embodiment, the compositions of the present invention indicatetheir capacity via a simple to recognize color change.

The present invention further provides methods and compositions for thedetection of moisture within an electronic device via a signalingmechanism for the purpose of diagnosing failure of the OLED, tofacilitate whether the failure of the device is due to moisture, OLEDmaterials, the manufacturing method, or some other failure mechanism.

These and various other features as well as advantages whichcharacterize the invention will be apparent from a reading of thefollowing detailed description and a review of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates one embodiment of the color change purifier materialas viewed through a transparent window in an OLED or other like device.

FIG. 2 illustrates one embodiment of the color change purifier materialas used to indicate a leak, i.e., source of contaminant, in an OLEDdevice.

FIG. 3 schematically illustrates a color change purifier materialattached to an inflexible OLED device.

FIG. 4 schematically illustrates a color change purifier materialflexibly attached to a substrate in an OLED device.

FIG. 5 illustrates the stable efficiency of Li-carboanion and lithiumhydride on divinyl benzene beads.

FIG. 6 illustrates the efficiency of Matheson Trigas OMX® material as afunction of temperature.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

The following definitions are provided to facilitate understanding ofcertain terms used frequently herein and are not meant to limit thescope of the present disclosure.

“Binder material” refers to any material used to secure the purifiermaterial into one mass wherein the purifier material is no longer inloose or powder form.

“Electronic component(s)” refers to any component found within anorganic light emitting diode or other like electronic device sensitiveto moisture, oxygen or other like oxygenated species including organictransistors. An illustrative electronic component is a cathode.

“Identifier alert” refers to a means for visual or other like indicationthat an electronic device has been exposed to a target impurity thatcould cause degradation in device performance.

“OLED” refers to an organic light emitting diode, but is usedinterchangeably with other electronic devices that are sensitive tomoisture and oxygen damage, for example organic transistor or OLEDdevices are used for illustrative purposes throughout the disclosureherein.

“Reduction, control or limitation” refers to a measurable decrease inthe concentration of a target impurity within a defined environment. Areduction can be from a first level of target impurity to a lower secondlevel of target impurity.

“Purifier material” refers to reactive agents having capacity to removewater and other oxygenated species from a local environment inaccordance with the present invention.

“Target impurities” refers to oxygen, water, CO, CO₂, NO, NO₂, N₂O₄,SO₂, SO₃, SO, S₂O₂, SO₄ and the like and mixtures thereof that candamage and/or reduce the lifetime of an electronic device, for examplean OLED.

The present invention provides compositions and methods for thereduction, control or limitation of moisture and other oxygenatedspecies from the environment of an OLED or other like electronic device.Embodiments of the present invention are also useful in limiting orpreventing moisture and other oxygenated species from entering theinterior environment of an OLED or other like device. The presentinvention provides “purifier materials” that facilitate the reduction,control and/or limitation of moisture and other oxygenated species froman electronic device. In preferred embodiments the purifier materialremoves target impurities substantially irreversibly until the purifiermaterial reaches its capacity.

The present invention also provides compositions and methods thatpresent a visual signal that a purifier material has reached itscapacity and should be replaced, or signal that the device in which thematerial is located is no longer protected by that purifier material.The present invention also provides electronic devices having integratedpurifier materials, and in preferred embodiments, electronic deviceshaving integrated purifier materials that change color with exposure toimpurities, e.g., water and other oxygenated contaminants.

Purifier Materials of the Invention:

One embodiment of the invention describes a purifier material, i.e.,reactive agent, that is chemically bonded or physically dispersed onhigh surface area substrates to increase contact toward a targetimpurity or impurities. Embodiments of the invention will increase theefficiency of removing moisture and other oxygenated species from anOLED containing environment. Purifier materials are integrated intoelectronic devices to limit or eliminate target impurities from theinterior environment of a target device.

As briefly noted above, other devices susceptible to moisture damage arealso included within the scope of the present invention, although mostof the description will focus on electronic devices, and in particularto OLED devices.

Examples of purifier materials within the context of the presentinvention include but are not limited to, macroreticulate polymerbonding to metals as previously described in U.S. Pat. Nos. 4,603,148,4,604,270, 4,761,395, 4,950,419, 5,015,411, 5,037,624, 5,340,552,5,385,689, and 6,077,487, metal hydrides, P₂O₅, finely dispersedtransition metals and metal oxides on high surface area substrates aspreviously described in U.S. Pat. Nos. 6,733,734, 6,110,258, 6,461,411,6,241,955, and 6,059,859, and other purifier materials such as highsurface area transition metals and carbon based materials as previouslydescribed in U.S. Pat. Nos. 6,521,014, 5,961,750, and 6,425,946, and6,066,591 Each of these patents is herein incorporated by reference inits entirety.

Several commercially available examples of these types of materials,included in the context of the invention, are Matheson Trigas' OMX®,IMX®, and O-Lifeguard®D resin based materials, Mykrolis Corporation'sfamily of reactive micro matrix (RMM) purification materials, asdescribed in Mykrolis Microelectronic Applications Note MA020 Å, andPall Corporation's Areskleen™ material. The present invention includes,but is not limited to, the following macroreticulate polymer basedpurifier materials for use in OLEDs. Macroreticulate polymer bonding tometals of the present invention may be represented by the formula (1).The symbol Ar represents an aromatic hydrocarbon radical containing fromone to three rings; R₁ and R₂ are the same or different and are selectedfrom the group consisting of hydrogen, alkyl hydrocarbon radicalscontaining from 1 to 12 carbon atoms, methylene-bridged benzophenoneradicals, alkali or alkaline earth metal salts of methylene-bridgedbenzophenone; methylene-bridged fluorenone radicals and alkali oralkaline earth metal salts of methylene-bridged fluorenone. M isselected from the group consisting of lithium, potassium, sodium alkylmagnesium, and alkyl zinc where the alkyl groups are hydrocarbon alkylradicals containing from 1 to 12 carbon atoms, said macroreticulatepolymer having within its pores a metallating agent selected from thegroup consisting of alkyl lithium, alkyl sodium, alkyl potassium,dialkyl magnesium, alkyl magnesium halide and dialkyl zinc, where thealkyl group is an alkyl hydrocarbon radical containing from 1 to 12carbon atoms; alkali or alkaline earth metal salts or benzophenone andalkali or alkaline earth metal salts of fluorenone, alkali or alkalineearth metal hydrides.

Macroreticulate polymers bonding to metals can be prepared from anactive scavenging species, present on the support, formed by depositionon the support of an organometallic precursor compound of the formulaM(R)₂, wherein M is a metal from Group 1A, IIA and IIIA, and R is alkyl,and pyrolysis thereof on said support at elevated temperature.

Ar can be considered as support material. Macroreticulate polymers canbe formed from monomers selected from the group including but notlimited to styrene, vinyltoluene, vinyliscpropylbenzene,ethylvinylbenzene, vinylnaphthalene, alpha-methylstryene,betamethylstyrene, divinylbenzene and divinylnaphthalene, andstyrenedivinylbenzene. Other support materials include but are notlimited to alumina, silica, aluminosilicates; kieselguhr; carbon; andmixtures, alloys, and mixtures thereof.

Organometallic precursors are selected from the group including but notlimited to butyllithium, dibutylmagnesium, trimethylaluminum,triethylaluminum, and diisobutylaluminum hydride.

Purifier materials of the present invention may also include metals andmetal hydrides of Group 1A, IIA and/or IIIA dispersed on organic supportmaterial, carbon support material and inorganic support material.

With regard to the inorganic support material, the inorganic supportmaterials comprises a high surface area of alumina, silica, zeolite,aluminosilicate, metal oxides such as zirconium oxide, manganese oxide,iron oxide, titanium oxide. Also, reduced state transition metal oxidesselected from the group including but not limited to oxides ofmolybdenum, antimony, bismuth, tin, chromium, cobalt, copper, tungsten,manganese, iron, nickel, vanadium, and chromium, and mixture thereof canbe a support material.

Carbon support materials are typically activated carbon and graphite,although other like materials are envisioned to be within the scope ofthe invention.

In general, support materials of the invention preferably have more than10 m²/g of surface area, although lesser amounts can be useful. Thesupport materials can be used in the forms including but not limited topowder, pellets, tablet, granulate, sphere, film and sheets. The size ofthese pellets, tablet, granulate and sphere typically are in the rangeof 1 nanometer to 1 centimeter, and can have uniform or non-uniformshapes.

Accordingly, this invention includes finely dispersed transition metalsand metal oxides on high surface area substrates.

The purifier materials of this invention can also comprise a thin layerof reduced forms of an oxide of a metal and/or metals deposited orcoated onto the surface of organic, inorganic and carbon substrates. Thereduced forms of the metal oxide thin layer coating include one or morereduced oxides of the metal in which the oxidation state of the metal islower than the maximum oxidation state of the metal. In addition to thereduced oxides of the metal, the thin layer may further include thecompletely reduced form of the metal (i.e., the metal in a zerooxidation state).

This invention further provides methods of removing one or morecontaminants from OLED environment using purifier materials of thisinvention that comprise a high surface area of inorganic, organic andcarbon substrate having deposited thereon a thin layer of one or morereduced forms of a metal oxide. Typically the metal oxide is selectedfrom the group consisting of oxides of molybdenum, antimony, bismuth,tin, chromium, cobalt, copper, tungsten, manganese, iron, nickel,vanadium, chromium, alkaline metal, alkaline earth metal and mixturesthereof.

In another embodiment of this invention, the purifier material comprisesa high surface area of inorganic, organic and carbon substrate havingdeposited thereon a thin layer of one or more metals, wherein said metalis a transition metal and is selected from the group consisting ofmolybdenum, antimony, bismuth, tin, chromium, cobalt, copper, tungsten,manganese, iron, nickel, vanadium, chromium, alkaline metal, alkalineearth metal and mixtures thereof.

The purifier materials of the present invention have capacity forreducing the level of target impurities such as oxygen, moisture, CO,CO₂, NO, NO₂, N₂O₄, SO₂, SO₃, SO, S₂O₂, and SO₄ from an interiorcompartment of an OLED or the environment where OLED are packaged fromparts-per-million levels down to sub-parts-per billion levels. Inpreferred emboidments, removal of target impurities to the purifiermaterial is substantially irreversible, but limited by the capacity andamount of purifier material used within any particular device. As such,once the capacity of all the purifier material within a device has beenexceeded the purifier material will no longer remove or control targetimpurity levels within the device.

As is described in greater detail below, the purifier materials of thepresent invention are incorporated into OLED and other like electronicdevices to prevent and/or limit the damage caused by moisture and otherlike oxygenated contaminants to electronic components within the device.

In an alternative embodiment of the present invention, a “color changepurifier material” is positioned to allow visual inspection of thematerial within the OLED so as to indicate when the material has reachedcapacity, i.e., the color change purifier material changes color as itabsorbs/adsorbs/traps target impurities from a first color to adifferent second color. Typical color change materials are blended orincorporated into purifier materials of the present invention, thecombination of a purifier material and color change indicator isreferred to herein as a color change purifier material. In general,color change purifier materials include a ratio of from about 1:100color change material:purifier material to 1:2 color changematerial:purifier material, and is preferably about 1:4 color changematerial:purifier material. In this respect, color change purifiermaterials can provide a gradation of color to show the current capacityof the material and whether the material needs to be replaced, whereappropriate, or when the material is simply exhausted, where replacementis not feasible.

Color change of the color change material is due to reaction with anoxygenated species such as moisture or oxygen, can indicate a leakpathway in the device prior to device failure. The device failuremechanism can be directly correlated to the moisture and oxygenconcentration within the device by a simple visual inspection of thecolor changing material within the device. In this manner, if a devicefails due to other mechanisms such as high current density or inherentproblems with the light emitting materials, it will be possible todelineate this failure mechanism from device failure caused by moistureand oxygen degrading electronic components within in the device.

By combining the stated purifier materials above with a color changematerial, the color is changed due to adsorption of moisture on it, andit can thereby provide a lifetime indication of the purifier material. Acolor change purifier material that changes it's color due to theadsorption/absorption/trapping of moisture can be a material includingbut not limited to cobalt chloride and other transition metal complexes,phosphorus pentaoxide (P2O5), and other like compounds. In addition,several purifier materials, including Matheson Trigas' OMX material havethe inherent property of changing color upon interaction with moistureand other oxygenated species.

As an illustrative example of a color change purifier material useful inthe context of the present invention, cobalt chloride can beincorporated into a purifier material of the present invention andfurther incorporated into a target electronic device along or viewablethrough a transparent panel or window. The cobalt chloride is a colorindicator that will change color due to interaction with targetimpurities. The cobalt chloride remains blue in the absence of targetimpurities, an indication that the electronic device is protected fromtarget impurities. However, if the cobalt chloride turns pink or beginsto transition to a pink color, there is a real danger to the electronicdevice from target impurities, e.g., target impurities are present inthe electronic device and the purifier material has reached capacity forremoving the material. In this situation the electronic components ofthe device are no longer protected from target impurities.

Further, with regard to the color change purifier materials, somematerials change color due to a change in the materials oxidation state(especially where the color change purifier material is a transitionmetal complex). However, color of the material can also or alternativelybe affected by a change in the coordination of different molecules orligands to various metal complexes.

Note that combinations of color change purifier material and purifiermaterial, discretely positioned within a device, can be used in thecontext of the present invention.

In another embodiment of the invention, the purifier material comprisesa high surface area of reduced state metal oxide. In this embodiment,substrate itself is a reactive agent. Said metal oxide is metal oxide ofa transition metal and is selected from the group including but notlimited to molybdenum, antimony, bismuth, tin, chromium, cobalt, copper,tungsten, manganese, iron, nickel, vanadium chromium, and mixturesthereof.

Examples of substrates suitable for purposes of this invention include,but are not limited to, alumina, amorphous silica-alumina, silica(SiO₂), aluminosilicate molecular sieves, titania (TiO₂), zirconia(ZrO₂), high surface area of transition metals, stylene polymer, anytypes of high surface polymer, and carbon. The substrates arecommercially available in a variety of shapes of different sizes,including, but not limited to, beads, sheets, extrudates, powders,tablet, granules, etc. The surface of the precursor substrate can becoated with a thin layer of a particular form of the metal (e.g., ametal oxide or a metal salt) using methods known to those skilled in theart, including, but not limited to, incipient wetness impregnationtechniques, ion exchange methods, vapor deposition, spraying of reagentsolutions, co-precipitation, physical mixing, etc. In addition, manysuch coated precursors are commercially available.

The terms “metal having a first oxidation state” and “first form of ametal” are used interchangeable and refer to the form of the metalcomprising the thin layer coated onto the surface of the precursor. Forexample, in one embodiment the precursor coating comprises a thin layerof a metal having a first oxidation state which is consequently treatedto produce a purifier material comprising a reactive or nonreactivesubstrate coated with a thin layer of one or more oxides of the metalhaving a second, lower oxidation state. In another embodiment, theprecursor coating comprises a first form of the metal wherein the firstform is other than a metal oxide. In this embodiment, the precursor istreated to produce a purifier material comprising a reactive ornonreactive substrate coated with a thin layer of a metal oxide havingthe same oxidation state as the first form of a metal. Examples of a“metal having a first oxidation state” and “first form of a metal”include, but are not limited to, an oxide, a salt, an acid, an organiccomplex or an inorganic, complex of the metal. Examples of metalssuitable for purposes of this invention include, but are not limited to,vanadium, molybdenum, antimony, bismuth, tin, cerium, chromium, cobalt,copper, tungsten, manganese, iron, and mixtures thereof. Suitable metalsalts from purposes of this invention include, but are not limited to,nitrates, carbonates, oxalates, etc.

In another embodiment, the purifier materials further comprise analkaline metal, alkaline metal oxide, or alkaline metal hydroxidedeposited over the metal oxide thin layer and/or mixed in with the metaloxide thin layer. Alkaline metals include lithium, sodium, potassium,rubidium, and cesium.

In general, the final purifier material comprises about 1 to 90% of thereduced forms of the metal and the metal oxide and about 10 to 99% ofthe substrate. For example, in one non-limiting embodiment the finalpurifier material comprises about 5-30% of the reduced forms of themetal and the metal oxide and about 70-95% of the substrate. Further,the total surface area of the thin layer of the final purifier materialis generally between about 20 m 2/g and 1200 m²/g. A preferredembodiment has a total surface area of final purifier material of about800 m²/g. In another embodiment, the total surface area of the thinlayer of the final purifier material is between about 10 and 300 m²/g.

As used herein, the terms “reduced forms of an oxide of the metal” and“metal oxide having a second, lower oxidation state” refer to one ormore oxide forms of the metal in which the metal has a lower oxidationstate than that of the metal in the precursor thin layer. The thin layerof a final purifier material of this invention may contain one or moredifferent metal oxides. Thus, the term “second oxidation state” is notlimited to one specific oxidation state, but rather encompassesdifferent forms of the metal, wherein each of the metal oxides in thepurifier material coating has an oxidation state that is lower than thatof the metal of the precursor coating. The term “reduced forms of anoxide of a metal” also encompasses zero valent metal.

For example, in one non-limiting embodiment the metal oxide thin layerof a precursor is a molybdenum oxide. Molybdenum is known to form atleast four oxides, which are, in descending order of oxidation state ofmolybdenum, MoO₃, Mo₂O₅, MoO₂, and Mo₂O₃. Thus, if the precursorcomprises a thin layer of MoO₃ (in which the oxidation state of Mo is+6), then the reduction step can produce a final purifier materialhaving a thin layer that contains one or more of the lower oxides ofmolybdenum, including Mo₂O₅, MoO₂, and Mo₂O₃. In addition to the one ormore reduced forms of molybdenum oxide, a percentage of the thin layerof the purifier material may also contain metallic molybdenum (Mo),i.e., molybdenum in its zero oxidation state. The composition of thethin layer of the purifier material will of course depend on the amountof time the precursor is exposed to hydrogen gas during the reductionstep, as well as the temperature during the reduction (see below).Alternatively, if the precursor comprises a thin layer of Mo₂O₅ (inwhich the oxidation state of Mo is +5), then the thin layer of the finalpurifier material may comprise one or more of the lower oxides ofmolybdenum, including MoO₂ and Mo₂O₃, and may further contain molybdenumin its zero oxidation state (Mo).

It is not necessary that the first oxidation state of the metal in theprecursor thin layer be the maximum oxidation state for that metal.However, at least a portion of the metal in the final purifier thinlayer is a reduced metal oxide. That is, in one embodiment at least aportion of the metal in the thin layer of the final product is betweenthe first oxidation state of the metal of the precursor layer and thezero oxidation state of the metal.

In yet another embodiment of this invention for removing targetimpurities from OLED environment and manufacturing process, the purifiermaterial comprises a substrate having deposited thereon a thin layer ofmetals and one or more reduced forms of an oxide of a metal from Group3b metals (scandium, yttrium, and lanthanum) Group 4b metals (titanium,zirconium and hafnium), vanadium, and lanthanide metals (cerium,praseodymium, neodymium, samarium, europium, gadolinium, terbium,dysprosium, holmium, erbium, thulium, ytterbium and lutetium).

Methods of Manufacture

The present invention provides methods of removing target impuritiesincluding, but not limited to, oxygen, moisture, CO, CO₂, NO, NO₂, N₂O₄,SO₂, SO₃, SO, S₂O₂, and SO₄ from OLED devices, organic transistors andother moisture sensitive devices, and from the manufacturing process offabricating OLED devices. The purifier materials produced by the methodsof this invention are capable of reducing the level of contaminants inOLED environment and manufacturing process from parts-per-million levelsdown to sub-parts-per-billion levels.

In one embodiment of the invention, a purifier material is produced by amethod comprising:

-   -   (a) providing a precursor comprising a high surface area        substrate having deposited thereon a thin layer of a metal of a        first oxidation state;    -   (b) heating the precursor under a flow of inert gas like        nitrogen at a temperature between about 100° C. and 600° C. for        a period of time; and    -   (c) treating the precursor from step (b) under reductive        conditions sufficient to reduce the oxidation state of the metal        in the precursor thin layer, thereby producing a purifier        material comprising a substrate having deposited thereon a thin        layer of one or more reduced forms of metals and an oxide of the        metal of a second oxidation state, wherein the second oxidation        state is lower than the first oxidation state.

The purified material can then be incorporated into a target electronicdevice or be temporarily used to prevent moisture and like contaminantsfrom entering the OLED during the manufacturing process. Purifiermaterials of the invention can be incorporated into glues, binders,tapes, films and other like materials for use in an OLED (see below). Ineach case, an appropriate amount of purifier material is incorporatedinto the device to facilitate the lifespan of the device.

Devices

Note that the following description of electronic devices incorporatingcolor change purifier materials can be expanded to include electronicdevices incorporating any purifier material of the present invention.The purifier materials would provide the benefits of limiting oreliminating target contaminants but without an indicator of the deviceor purifier material lifespan. However, only color change purifiermaterials are addressed below in the context of the disclosure, but itis envisioned that non-color change purifier materials incorporated intoOLED devices are within the scope of the present invention.

Currently, OLED's and other display devices utilize desiccants withinthe device to capture the moisture once the moisture permeates into theinterior of the device. The materials described in previous art havebeen selected from the group consisting of alkaline metal oxides,alkaline earth metal oxides, molecular sieves, silica, zeolites,sulfates, metal halides, perchlorates and metals with work functionsless than 4.5 eV. Although these materials will remove moisture from thedevice, these materials are inferior to purifier materials of thepresent invention that could be used within the OLED devices. Thepurifier materials of the present invention are better suited for thisapplication, and have been described previously in this disclosure. Inaddition, previous art desiccants do not provide a signal as to theircapacity or to the actual presence of target impurities during use.

One of the advantages and novelty of purifier materials of the presentinvention is to serve or act as diagnostic tools for moisture or othertarget impurity permeation into an OLED. Moisture has been reported tobe the root cause of failure for most electronic devices, especiallyOLEDs. Moisture can degrade multiple components within a device such asthe cathode, the hole injection layer, or the emissive layer. It hasbeen reported by Borrows et. al, APL, 65, 2922 (1994) that eliminationof moisture from the device reduces dark spot formation within thedevice. A dark spot can be characterized by a pixel location that nolonger emits light from that location or the emission area has beenreduced significantly. Other previous work by McElvain et al, JAP, 80,6002 (1996) demonstrated dark spot formation when moisture enters andcauses cracks in the cathode. Since the cathode is typically a metalwith low work functions, deposited between the polymeric materials andthe conductive substrate of the device, moisture will oxidize thecathodic material and cause delamination of the cathode from theconductive substrate. Once delamination of the cathodic material occursthe device will no longer function in that area since electrical currentcan no longer flow through the device in that area.

Although moisture, and to a lesser extent, oxygen has been reported tobe a failure mechanism for OLED and similar devices, other failuremechanisms exist within the device. Aziz et al, Science, 283, 1900(1999) demonstrated that unbalanced charges or excessive holes in thedevice caused a rapid decay of the luminescence. There are many otherfailure mechanisms formulated for the less than desired lifetimes of thedevices. Therefore, the color change purifier materials proposed in thisinvention have a unique and distinct advantage over traditionally usedmaterials for this application. Since some of the purifier materialsproposed in this invention have the ability to drastically change colorsonce exposed to moisture, these types of materials can serve asdiagnostic tools for the failure mechanism of the device. FIG. 1illustrates how the color change purifier material changes color, orshade of same color, once the material has been exposed to an oxygenatedor other like species (as indicated by a black and white scale in theFigure).

As shown in FIG. 1, light colored spheres on the left 100 indicate thatthe color change purifier material has reacted with water and haschanged colors from a dark material to a light material. The curved line102 represents the boundary where moisture has permeated. To the rightof the curved line, the color change purifier material 104 remainsun-reacted and available to absorb moisture as it permeates in from theleft side of the diagram. If the entire panel of color change purifiermaterial had changed color, the panel would indicate that the devicewithin which the material is located would no longer be protected fromtarget impurities.

It is clearly evident that the use of desiccants is necessary to extendthe life of the OLED devices, as shown in previous work. USDC FlexibleDisplays and Microelectronics Conference Proceedings, Feb. 10, 2004,Phoenix, Ariz., or The Global Flat Panel Display Industry “2003”, NormanBardsley, U.S. Display Consortium, 2003, Chapter 17, pp. 67-69. The useof color changing purifier materials can offer the ability to determinewhen the device is exposed to moisture prior to device failure.

Since the nature of some of the devices are to emit light, all or mostaspects of at least one side of the device must be transparent orsubstantially transparent. However, a much more desired situation iswhere both sides of the device are transparent. In cases where bothsides of the electronic device are transparent (as is the case for topemitting OLED devices), it may be possible to disperse the color changepurifier material of the invention around the device in a pattern thatgoes around the outer circumference of the light emitting device. It mayalso be possible to disperse the color change purifier material in agroove inside a glue line of the device such that the material standsbetween the OLED device and the sealant. Furthermore, it may be possibleto mix the aforementioned inventive color change purifier materials inthe glue to sealant or epoxy of the device. Therefore, it should bepossible to disperse color changing materials within such a device andvisually determine when the material is consumed and more importantlywhen the device will then be exposed to moisture. This situation allowsfor the direct correlation of moisture concentrations to devicelifetime. In cases where the color change purifier material is patternedaround the outer circumference of the device, defects can be visualizedvia any areas where the color change purifier material changes color toindicate target impurity retention.

In other embodiments of the present invention, the device may include asmall window for viewing only a portion or fraction of the color changepurifier material, for example view one or more discrete spheres orwafers. A user could thereby use the window as a relative indicator ofthe state of the purifier material within the device. Further, mixturesof color change purifier material and non-color change purifier materialcould be positioned within the same device—as long as a portion of thecolor change purifier material is visible and indicative of the presenceof target impurities within the device.

In addition to the methods described previously, it may also be possibleto disperse the purifier materials into the actual device layers such asthe hole and electron injection layers and the emissive layer, if thepurifier material is small enough not to affect the electrical andperformance properties of the device. The purifier material could bedispersed into the various layers during the time of manufacture for thevarious layers. For example, many of the layers are deposited via a spincoating technique. By introducing the purifier materials into thecasting solution used for spin coating, the active purifier materialscan be introduced into the various layer during the time of manufacture.Similarly, the purifier materials can be introduced into themanufacturing process of other deposition techniques.

Determinations of the amount of purifier material or color changepurifier material to include within a target devices are based on thesource of the purifier material, including the materials capacity (seepurifier material section above), the size of the device, thecircumference of the device, for example the glue line circumference ofthe device, the permeability of the binder material, and the potentiallevels of target impurities within the device environment. For example,approximately 0.5 ml of a 100% organometallic reactive agent and amacroreticulated substrate is required for a 2 inch device (e.g., 0.5 mlMatheson Trigas' OMX® per 2 inch device).

In addition, it is possible to determine the performance status of thecolor change purifying material prior to introduction into theelectronic device. This is accomplished visually or by other opticalmethods. Visual color changing materials within OLED devices could alsobe used as a final quality control check prior to shipping the device toa customer. The quality control check could be operated withoutoperating and illuminating the device, but via a simple inspection ofthe color change purifier material. Traditional desiccant materials haveno indication if the material has been properly activated and is readyfor use within the device. It is possible that these traditional typesof materials require re-activation by the OLED device manufacturer toensure the material is dry and ready to function properly within thedevice. This costly and time consuming process could be avoided if itcan be ascertained that the material is activated and ready for use byvisual observations or optical methods of detection. The aforementionedvisual observation or optical method of detection can be easilyimplemented with the material embodiments proposed and described withinthis invention. Although it has not been reported what critical moistureconcentrations are necessary to avoid device degradation, it isgenerally believed that ppm levels of moisture can negatively affect thedevice performance. USDC Flexible Displays and MicroelectronicsConference Proceedings, Feb. 10, 2004, Phoenix, Ariz., or The GlobalFlat Panel Display Industry “2003”, Norman Bardsley, U.S. DisplayConsortium, 2003, Chapter 17, pp. 67-69. By using the color changepurifier materials described within this disclosure it is possible topredict when the device will fail since the color change purifiermaterial will likely change color prior to device lifetime failure. Thisfeature is advantageous for end users who require 100% uptime for thelight emitting device. Also, this feature could be used to give awarning or signal to the end user that the device is near failure andanother device should be procured shortly.

The use of color changing purifier materials described within thisinvention for these types of applications has the ability to indicatewhen the purifier material is consumed and more importantly, predictwhen the device will be exposed to moisture and ultimately fail.However, in addition to serving as a device lifetime predictor andindicator, the color changing purifier material can serve as adiagnostic tool for the fabrication of the devices. Since the materialschange colors and can be dispersed throughout the devices, the colorchanging purifier materials will provide direct information on locationof moisture and oxygen intrusion (see FIG. 1). This information couldpoint to manufacturing defects, and material defects, that wouldotherwise go un-noticed. The ability to determine problematic locationswithin the device is critical in identifying solutions to the problem ofdevice failure. It may also be possible to test different materials suchas glues, epoxies, sealants, barrier layers, etc., in side by side testswithin one device to obtain material performance data. It may also bepossible to identify non-uniformities in the manufacturing process suchas glue line thickness and width, non-uniform placement of the materialswithin the device, and many other failure mechanisms. Additionally, ifthe device fails and the color changing purifier material indicates thatthere is no moisture within the device, the design engineer canimmediately discard the failure mechanism of moisture intrusion into thedevice as the source of failure. By eliminating the moisture as afailure mechanism, the design engineer can save valuable time andresources by not investigating moisture as a root cause of failure.Typically, devices are built to completion and then undergo acceleratedlifetime tests. This test can take up to several months to complete andis costly since the entire device must be fully fabricated usingvaluable equipment time and valuable material. It is believed with theadvent and utilization of the color changing purifier materials, much ofthe testing conducted to determine the moisture effects on the devicecan be conducted faster, less expensive, with higher sensitivity, andwith more definitive and conclusive results. FIG. 2 shows that if thecolor changing purifier material is dispersed throughout the OLEDdevice, it can serve as a method to determine where moisture isintruding the fastest into the device. This allows the device designersto select new designs and new materials that minimize moisture intrusionareas.

In particular, and for illustrative purposes, FIG. 2 illustrates a colorchanging purifier material reacting with moisture or oxygen from acorner defect in the OLED device (see arrow 200). The change in thecolor demonstrates the location and probable leak mechanism within thedevice (as compared to arrow 202). Note substrate 204 and OLED layers206.

The color change purifier materials described in the present inventionalso have a greater propensity to be used in fully flexible devices.Current traditional desiccant materials are used in the form ofinflexible tablets or films that can break or delaminate during flexibleoperations of the device. Alternatively, prior art has demonstrated theuse of liquids to disperse the materials into the devices in the form ofpastes, binders, or gels. The color change purifier materials for thisinvention includes but is not limited to unconnected discrete shapes inthe form of spheres, rods, and irregular shapes or any shape where inone discrete material is not connected to each other as in thin films,tablets, sheets, or wafers. Note also that the color change purifiermaterials can also be shaped to provide a symbol associated withmaterial exhaustion, for example, the material can spell out a word,e.g., GOOD, which disappears over the lifetime of the device, when thematerial is no longer providing protection to the device, oralternatively, changes color upon exhaustion to spell out PINK MEANSEXHAUSTED.

The use of binders or pastes as described in U.S. patent application20030037677 is also suited for this application, since moisture mustfirst slowly permeate through the binder before it can reach a colorchange purifier material site that will react or absorb the moisture.Binders used for this type of application have been previously discussedin U.S. patent application 20030037677, which is incorporated byreference herein in its entirety. Note that the volatile nature of thebinders used can absorb onto the color change purifier materials andcompete with water for the color change purifier material sitesresponsible for removal of water. Although color change purifiermaterials can be fixed within a device by glues, epoxies or binders, itis believed that other methods can be used to immobilize thesematerials. Such methods can permanently or temporarily immobilize thematerial within the device. The methods of moving or immobilizing thecolor change purifier material within the devices include but are notlimited to electric fields, magnetic fields, vacuum positioning or aircurtains. These moving or immobilizing processes are generally knownwithin the art.

In a preferred embodiment, spherically shaped organometallic beadsdescribed by U.S. Pat. No. 4,950,419, by Tom Glenn, et al. (which isherein incorporated by reference in its entirety), can be dispersed intothe device in a manner where the color change purifier beads areattached to the substrate via a thin layer of flexible adhesive, solventor glue. The beads are immobilized onto a flexible adhesive and caneasily tolerate mechanical stresses involved with flexing and bending ofthe substrate. FIG. 3 illustrates how the beads are immobilized onto aflat substrate such as glass or metal. Purifier material 300 is placedbetween a protective glass 302 and a polymer cathode 304. The material300 is incorporated into an adhesive film 306. Also shown are theelectron injection layer 308, emissive polymer layer 310, hole injectionlayer 312 and polymer anode 314.

The need for flexible electronic displays and devices has beenconsidered for many years. The flexibility will cause the color changepurifier material to have new applications, but more importantly, thedevice can be manufactured in a process described as roll to rollprocessing. The Global Flat Panel Display Industry “2003”, NormanBardsley, U.S. Display Consortium, 2003. With the advent of roll to rollprocessing for the OLED and similar devices, the cost of manufacturingis expected to decrease significantly compared to current wafer batchprocessing. Thus, the need for a fully flexible device is immediate andsignificant. FIG. 4 shows how the color change purifier material ‘beads’400 can be attached to a flexible substrate 402 and conform to thenon-uniform and uneven surface, and remain attached during flexing,motion and movement.

FIG. 4 is a schematic diagram illustrating the Matheson Trigas OMX®purifier material attached to a fully flexible OLED device 406. Alsoshown are the polymer cathode 408, electron injection layer 410,emissive polymer layer 412, hole injection layer 414 and polymer anode416.

The beads 400 will not be affected adversely if the substrate flexes,bends or is stressed. In addition to spherically shaped purifiermaterials, the materials can take the form of any shape that best suitsthe device configuration and geometry. In addition to forming the beadsinto geometric shapes that are best suited for the device geometry, theorganic or plastic based materials can be formed by various methodsincluding but not limited to thermo-plastically formed, extruded, orcompression molded into different macrogeometric shapes that will fitthe desired shape and form. In another preferred embodiment, the rawmaterial plastic beads described by U.S. Pat. No. 4,950,419, which isincorporated herein by reference in its entirety, by Tom Glenn, et al.,can first be formed into a desired shape such as a 1 inch square that isless than 1 mm thick. The flat square shape can then undergo thechemical reaction that allows the plastic starting material to act as adesiccant. Once the plastic square shape has been reactively andchemically activated, it can be placed into the device as a singularpiece of material that will react with water and oxygen as theseimpurities enter the device. The singular piece of formed material canthen be immobilized into the device by glues, adhesives, sealants, andbinders. In a preferred embodiment, the purifier material is shaped as abead and applied in an organic solvent or adhesive which is evaporatedor dried to operatively attach the bead to the protective polymer glass.In another preferred embodiment, the purifier material is encapsulatedinto a film or diffusion barrier in which the purifier is protected fromthe atmosphere until time of manufacture. Alternatively, the purifiermaterial can be encapsulated in a tape of film and the entire tape orfilm then gets incorporated into the device.

The following three examples are illustrative in nature and are notmeant to limit the scope of the different embodiments of the invention.

EXAMPLES Example 1

Deposition of Cerium Nitrate onto Alumina by Incipient WetnessImpregnation

Alumina was modified by Ce(NO₃)₃:6H₂O to form a cerium oxide coating(150-200 m² g) on the alumina using an incipient wetness impregnationtechnique. About 222 mL (122.77 g) of alumina beads was dried in avacuum oven at about 110° C. overnight, then cooled to room temperatureunder vacuum. To this was added a solution of 19.0 g Ce(NO₃)_(3:6)H₂O in36.8 g H₂O dropwise in a 600 mL beaker. After about 30-40 minutes, allof the solution was added without any observation of outside wetting ofthe alumina beads. The material obtained was capped by aluminum foil andallowed to equilibrate at room temperature for about 20 hours. Thematerial was then heated to about 110° C. for about 20 hours in a vacuumoven. A sample of the obtained (dry) Ce(NO₃)₃:6H₂O/Al₂O₃ (containingabout 5% Ce) was analyzed by thermogravimetric analysis using a TGA-7thermogravimetric analyzer from PerkinElmer. Two peaks were obtained,one at about 200° C. and the other at about 400° C. The peak at about200° C. is moisture (as in Al₂O₃) and the peak at about 400° C. (notfound in Al₂O₃) was due to nitrate decomposition. Decomposition startsat about 280° C. (at 20° C./min heating rate) and is complete at about550° C.

Example 2

Efficiency and Capacity Changes of Materials as a Function of theTemperature

The efficiency of molecular sieve material was tested for capturingwater at different temperatures and it was found that the capacity formoisture varied significantly as a function of temperature as shown inTable 1. The temperature dependence is an important parameter since itcan affect the device operation. It is well known that materials thatoperate on the principle of physisorption such as molecular sieves,silica, zeolites, etc., can reversibly absorb moisture. At roomtemperature molecular sieve 4 A will absorb 9.2 liters of moisture perliter of 4 A material. However, if the temperature of the material isincreased, previously absorbed moisture can now be emitted from thedevice causing the electronic device to fail. Since the applications forthe devices are hand held cellular phones, and portable devices, it canbe reasonably estimated that the device will be exposed to a largetemperature variations. Thus, it is believed that the materials based onphysisorption are not well suited for use within OLED and otherelectronic devices. TABLE 1 Capacity degradation of MS 4A due totemperature and efficiency. Efficiency EQM H₂O Capacity, liter H₂O/liter4A mol sieves at (ppm H₂O) Conc Psia 0° C. (32° F.) 25° C. (77° F.) 0.011.47 × 10⁻⁷ 3.3 1.7 0.1 1.47 × 10⁻⁶ 18.5 9.2 1 1.47 × 10⁻⁵ 43.0 30.0EQM = Equilibrium,Conc = ConcentrationAlternatively the material prepared as described herein did not show anydifference in efficiency and capacity at different temperatures as shownin FIG. 5 and FIG. 6. The material was prepared as follows.Macroreticulate polymer bonding to metal can be prepared by thefollowing method. Macroreticulate polymer backbone ispoly(styrenedivinylbenzene). Metallating agent is tert-butyllithium.Macroreticulate polymer scavenger containing pendant functional groupsis subsequently purified by heating to a temperature of about140.degree. to about 250.degree.C. for several hours.Polystyrene-divinylbenzene and tert-butyllithium are mixed in thecontrolled temperature bath to formulate Li-carbanion and lithiumhydride on the poly-styrene beads.

Since the OLED device lifetime is directly related to amount of moisturethat enters the device. The device lifetime is severely shortened whenmoisture comes into contact with the emissive and injection layers ofthe device. Once the OLED has been manufactured, it must be protectedfrom moisture by placing a desiccant next to the device andencapsulating the device and desiccant within a polymeric, metal orglass barrier designed to minimize the permeating of moisture. If thedevice is encapsulated with glass or metal, then the sealant used toattach the encapsulation lid to the glass or metal substrate becomes thearea in which significant levels of moisture permeate into the device.

The present invention should not be considered limited to the particularexamples described above, but rather should be understood to cover allaspects of the invention as fairly set out in the attached claims.Various modifications, equivalent processes, as well as numerousstructures to which the present invention may be applicable will bereadily apparent to those of skill in the art to which the presentinvention is directed upon review of the instant specification.

The content of all publications, patents, and patent documents describedand cited herein are incorporated by reference as if fully set forth.

Example 3

Non-Limiting and Un-Exhaustive List of Possible Substrates and ReactiveAgents Used for the Invention Described Herein. TABLE 2 Matrix ofExamples of Macroreticulated Substrates and Organometallic ReactiveAgents. styrene VT VIB EVB VN AMS BMS DVB DVN PPYR AKLL AKLS AKLP DAKLMAKLM DAKLZ AKL1-X AKL2-X AKL1-FLE AKL2-FLE AKL1-H AKL2-HExamples listed are not meant to be limiting or exhaustive in scope, butonly serve to be representative examples of some possible substrates andreactive agents. Substrates are listed across the horizontal axis whilethe reactive agents are listed across the vertical axis.

-   VT=vinyltoluene, VIB=vinyliscpropylbenzene, EVB=ethylvinylbenzene,-   VN=vinylnaphthalene, AMS=alpha-methylstryene, BMS=betamethylstyrene,-   DVB=divinylbenzene, DVN=divinylnaphthalene,-   PPYR=polypyridines such as poly(4-vinylpyridine),    poly(2-vinylpyridine), polyquinolines such as    poly(4-vinylquinoline), poly(2-vinylquinoline) and analogs thereof.

AKLL=alkyl lithium, AKLS=alkyl sodium, AKLP=alkyl potassium,DAKLM=dialkyl magnesium, AKLM=alkyl magnesium halide, DAKLZ=dialkylzinc, where the alkyl group is an alkyl hydrocarbon radical containingfrom 1 to 12 carbon atoms. ALK1-X=alkali metal salts where X representssuitable anions such as halogens, carbonates, sulfates, nitrates,oxalates or phosphates. ALK2-X=alkaline earth metal salts where Xrepresents suitable anions such as halogens, carbonates, sulfates,nitrates or phosphates, AKL1-FLE=alkali metal salts of fluorenone,AKL2-FLE=alkaline earth metal salts of fluorenone, AKL1-H=alkali metalhydrides and AKL2-H=alkaline earth metal hydrides. TABLE 3 Matrix ofExamples of Inorganic Substrates and Metallic Reactive Agents. ALSILCALUMINA SILICA MS TITANIA ZIRCONIA CARBON TRN-X AKL1-X AKL2-X AKL1-HAKL2-H LAN-X GET-ALY1 GET-ALY2Examples listed are not meant to be limiting or exhaustive in scope, butonly serve to be representative examples of some possible substrates andreactive agents. Substrates are listed across the horizontal axis whilethe reactive agents are listed across the vertical axis. Othersubstrates included but not listed in the table are yttria or vanadia.In addition metal salts that are listed as reactive agents can also beused as subtrates with or without further coatings or functional groups.Analogously, substrates can be used without further functionalizationfor the removal of moisture and other oxygenated species.

-   ALSILC=aluminosilicates and silica-alumina complexes,-   MS=Molecular Sieves of all types,-   TRN-X=transition metal salts such as vanadium, molybendenum,    antimony, bismith, tin, cerium, chromium, cobalt, copper, tungsten,    iron, nickel, manganese, zinc, zirconium, silver, cadmium, rhenium    and mixtures thereof where X represents suitable anions such as    halogens, carbonates, sulfates, nitrates, oxalates or phosphates.

ALK1-X=alkali metal salts where X represents suitable anions such ashalogens, carbonates, sulfates, nitrates, oxalates or phosphates.ALK2-X=alkaline earth metal salts where X represents suitable anionssuch as halogens, carbonates, sulfates, nitrates or phosphates,AKL1-H=alkali metal hydrides and AKL2-H=alkaline earth metal hydrides,LAN-X=lanthanide metal salts where X represents suitable anions such ashalogens, carbonates, sulfates, nitrates, oxalates or phosphates,GET-ALY1=getter alloys containing mixtures of zirconium, vanadium, iron,manganese, yttrium, lanthanum, Rare Earths or mixtures thereof.GET-ALY2=getter alloys containing mixtures of zirconium, cobalt, andrare earth metals, yttrium, lanthanum, and mixtures thereof.

Note that the substrates and reactive agents disclosed within Tables 2and 3 are not meant to be limited, but rather combinations can be mixedand matched between columns and rows.

The present invention should not be considered limited to the particularexamples described above, but rather should be understood to cover allaspects of the invention as fairly set out in the attached claims.Various modifications, equivalent processes, as well as numerousstructures to which the present invention may be applicable will bereadily apparent to those of skill in the art to which the presentinvention is directed upon review of the disclosure. This specificationcontains numerous citations to patents, patent applications andpublications. Each is hereby incorporated by reference for all purposes

1. An electronic device comprising: an interior compartment housing anelectronic component that is reactive to target impurities, thecompartment defining at least one transparent window; and a purifiermaterial within the interior compartment; wherein the purifier materialhas a first color indicating that the purifier material is reactive totarget impurities and a second color indicating that the purifiermaterial is not reactive to target impurities and wherein at least aportion of the purifier material can be viewed through the at least onetransparent window.
 2. The electronic device of claim 1 wherein thepurifier material is selected from the group consisting of anorganometallic reactive agent and a macroreticulated substrate and ametallic reactive agent and an inorganic substrate.
 3. The electronicdevice of claim 2 wherein the purifier material is a color changepurifier material that incorporates a target impurities indicatorcomprising cobalt chloride and wherein the cobalt chloride has at leasta first and second color that are different dependent on whether atarget impurity is present.
 4. The electronic device of claim 2 whereinthe purifier material is a color change purifier material thatincorporates a target impurities indicator comprising P₂O₅ and whereinthe P₂O₅ has at least a first and second color that are differentdependent on whether a target impurity is present.
 5. The electronicdevice of claim 1 wherein the electronic component comprises at least acathode and anode and wherein the purifier material is positionedbetween the cathode or anode and the at least one transparent window. 6.The electronic device of claim 1 wherein the electronic componentcomprises at least a cathode and anode and wherein the purifier materialis positioned outside of the cathode or anode and viewable through theat least one transparent window.
 7. The electronic device of claim 1wherein the electronic component comprises at least a cathode and anodeand wherein the purifier material is interspersed within a conductingpolymer layer between the cathode or anode and the at least onetransparent window.
 8. The electronic device of claim 1 wherein theelectronic device is selected from the group consisting of an organiclight emitting diode, an organic transistor, a flat panel display, aliquid crystal display and electronic paper.
 9. The electronic device ofclaim 1 wherein the purifier material comprises an organometallicreactive agent and a macroreticulated substrate.
 10. The electronicdevice of claim 1 wherein the purifier material comprises a metallicreactive agent and an inorganic substrate.
 11. The electronic device ofclaim 1 wherein the purifier material has a surface area of from about20 m²/g to about 1200 m²/g.
 12. The electronic device of claim 1 whereinthe purifier material has a shape selected from the group consisting ofpowder, pellets, cylinders, tablets, granulates, extrudates, rods,spheres and other irregular discrete shapes.
 13. The electronic deviceof claim 12 wherein the shape is sized from about 1 nm to about 1 cm indiameter.
 14. The electronic device of claim 1 wherein the purifiermaterial is deposited into a film, tape, sheet, tablet or wafer.
 15. Theelectronic device of claim 1 wherein the purifier material isincorporated into a glue, binder, or sealant.
 16. An identifier alertfor an electronic device comprising: a binder material; and a colorchange purifier material operatively attached to the binder material;wherein the binder material is formulated for attachment within aninterior portion of the electronic device and wherein the operativelyattached color change purifier material has the potential to changecolors when exposed to target impurities within the interior of theelectronic device.
 17. The identifier alert of claim 16 wherein thecolor change purifier material comprises a target impurities indicatorof cobalt chloride.
 18. The identifier alert of claim 16 wherein thecolor change purifier material comprises a target impurities indicatorof phosphorus pentaoxide.
 19. The identifier alert of claim 16 whereinthe binder material is glue.
 20. The identifier alert of claim 16wherein the color change purifier material comprises an organometallicreactive agent and a macroreticulated substrate.
 21. The identifieralert of claim 16 wherein the color change purifier material comprises ametallic reactive agent and an inorganic substrate.
 22. The identifieralert of claim 16 wherein the color change purifier material has asurface area of from about 20 m²/g to about 1200 m²/g.
 23. Theidentifier alert of claim 16 wherein the color change purifier materialhas a shape selected from the group consisting of powder, pellets,cylinders, tablets, granulates, extrudates, rods, spheres and otherirregular discrete shapes.
 24. An electronic device comprising: aninterior compartment housing at least one electronic component that isreactive to target impurities; and a purifier material within theinterior compartment; wherein the purifier material decreases targetimpurities within the interior compartment of the electronic device froma first level to a second level.
 25. The electronic device of claim 24wherein the second level is sub-parts per billion.
 26. The electronicdevice of claim 24 wherein the electronic device is selected from thegroup consisting of an organic light emitting diode, an organictransistor, a flat panel display, a liquid crystal display andelectronic paper.
 27. The electronic device of claim 24 wherein thepurifier material comprises an organometallic reactive agent and amacroreticulated substrate.
 28. The electronic device of claim 24wherein the purifier material comprises a metallic reactive agent and aninorganic substrate.
 29. The electronic device of claim 24 wherein thepurifier material has a surface area of from about 20 m²/g to about 1200m²/g.
 30. The electronic device of claim 24 wherein the purifiermaterial is deposited into a film, tape, sheet, tablet or wafer.
 31. Theelectronic device of claim 24 wherein the purifier material isincorporated into a glue, binder, or sealant.
 32. The electronic deviceof claim 24 wherein the electronic component comprises at least acathode and anode and wherein the purifier material is positionedbetween the cathode or anode.
 33. The electronic device of claim 24wherein the electronic component comprises at least a cathode and anodeand wherein the purifier material is positioned outside of the cathodeor anode.
 34. The electronic device of claim 24 wherein the electroniccomponent comprises at least a cathode and anode and wherein thepurifier material is interspersed within a conducting polymer layerbetween the cathode or anode.
 35. A method for detecting a targetimpurity entering an interior compartment of an electronic devicecomprising: fabricating an electronic device having a visibly accessiblecolor change purifier material positioned around the outer circumferenceof the interior compartment of the electronic device; and periodicallyviewing the color change purifier material for a change in color from afirst color to a second color; wherein the position of the second colorindicates the presence of a target impurity at the position of thesecond color.
 36. The method of claim 35 wherein the color changepurifier material is a combination of organometallic reactive agent anda macroreticulated substrate mixed with cobalt chloride.
 37. Anelectronic device comprising: an interior compartment housing anelectronic component that is reactive to target impurities, thecompartment defining at least one transparent window; and a purifiermaterial within the interior compartment; wherein the purifier materialdecreases target impurities within the interior compartment of theelectronic device from a first level to a second level.
 38. Theelectronic device of claim 37 wherein the purifier material is selectedfrom the group consisting of an organometallic reactive agent and amacroreticulated substrate and a metallic reactive agent and aninorganic substrate.
 39. The electronic device of claim 37 wherein theelectronic component comprises at least a cathode and anode and whereinthe purifier material is positioned between the cathode or anode and theat least one transparent window.
 40. The electronic device of claim 37wherein the electronic component comprises at least a cathode and anodeand wherein the purifier material is positioned outside of the cathodeor anode.
 41. The electronic device of claim 37 wherein the electroniccomponent comprises at least a cathode and anode and wherein thepurifier material is interspersed within a conducting polymer layerbetween the cathode or anode.
 42. The electronic device of claim 37wherein the electronic device is selected from the group consisting ofan organic light emitting diode, an organic transistor, a flat paneldisplay, a liquid crystal display and electronic paper.
 43. Theelectronic device of claim 37 wherein the purifier material comprises anorganometallic reactive agent and a macroreticulated substrate.
 44. Theelectronic device of claim 37 wherein the purifier material comprises ametallic reactive agent and an inorganic substrate.
 45. The electronicdevice of claim 37 wherein the purifier material has a surface area offrom about 20 m²/g to about 1200 m²/g.
 46. The electronic device ofclaim 37 wherein the purifier material has a shape selected from thegroup consisting of powder, pellets, cylinders, tablets, granulates,extrudates, rods, spheres and other irregular discrete shapes.
 47. Theelectronic device of claim 46 wherein the shape is sized from about 1 nmto about 1 cm in diameter.
 48. The electronic device of claim 37 whereinthe purifier material is deposited into a film, tape, sheet, tablet orwafer.
 49. The electronic device of claim 37 wherein the purifiermaterial is incorporated into a glue, binder, or sealant.